Income taxes.

No definition available.

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

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- Definition

Amount of unrecognized tax benefits.

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Income Taxes - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2017
Income Taxes [Line Items]
Effective income tax rate reconciliation, percent	19.50%	22.50%
Unrecognized tax benefits	$ 0.2
Unrecognized tax benefits that would impact effective tax rate	$ 0.2
Federal corporate income tax rate	21.00%		35.00%
Internal Revenue Service (IRS) \| Earliest Tax Year
Income Taxes [Line Items]
Open tax year	2015
Internal Revenue Service (IRS) \| Latest Tax Year
Income Taxes [Line Items]
Open tax year	2017
State Local and Foreign Jurisdictions \| Earliest Tax Year
Income Taxes [Line Items]
Open tax year	2014
State Local and Foreign Jurisdictions \| Latest Tax Year
Income Taxes [Line Items]
Open tax year	2017